A waterproof type substrate housing case, wherein a rectangular circuit substrate is hermetically stored in a housing constituted by a first case and a second case, mounted on a first side of the circuit substrate, comprising a connector housing made of resin in which part of it is exposed from the opening of the housing, as well as a plurality of connection terminals press-fitted into the inner and outer partition walls of the connector housing wherein one end of the connection terminal is connected to the circuit pattern of the circuit substrate, and the other end has conductive contact with the contact terminal of the mating connector as a method for integrating the first case and the second case, is known to eliminate the screw tightening structure with poor assembling workability, and to use a snap fit.
For example, according to FIGS. 3 and 4 of the “driver device and motor device” described in the following patent literature 1, the opening part 11a of the case 11 is sealed with a cover 12 via a seal member J, by fitting the tongue part 17 of the cover 12 and the hook part 15 of the case 11, the cover 12 is prevented from falling off. The hook part 15 is configured to attract the case 11 and the cover 12 by the action of the inclined engagement surface 15a. 
As a result, it is possible to suppress the deterioration of the sealing property while adopting the attachment structure by the snap fit, it is possible to prevent the case and the cover from being damaged and the increase in manufacturing cost can be suppressed, according to FIG. 1, an elastic clipping part formed by the hook part 15 and the tongue part 17 are provided at four positions on the four sides of the case 11.